1. Field of the Invention
The present invention concerns a patient positioning table of the type having a base part having a longitudinal axis and a support plate for supporting a patient, the support plate being displaceable in the direction of the longitudinal axis of the base part relative to the base part. The invention also concerns a computed tomography apparatus having such a patient positioning table.
2. Description of the Prior Art
For tomographic examination of a patient with a tomography apparatus, such as a magnetic resonance apparatus, a C-arm x-ray apparatus or (as described in detail in the following) an x-ray computed tomography apparatus, a patient is positioned on a support plate of a patient positioning table, the support plate normally being displaced relative to a measurement system of the tomography apparatus. For example, if a computed tomography apparatus is considered, the support plate of the patient positioning table can be displaced in the longitudinal direction through an opening of the gantry of the computed tomography apparatus. The radiological measurement system (formed by an x-ray source and an x-ray detector situated opposite thereto) is contained in the gantry.
If a patient who is not able to position himself or herself on the support plate (for example due to an injury or a physical limitation) is to be relocated from a bed aligned parallel to the patient positioning table onto the support plate of the patient positioning table, it frequently proves to be disadvantageous that the access to the support plate is limited for medical personnel either at the head or at the foot of the support plate due to the proximity to the gantry. Furthermore, the sole longitudinal movement capability of the support plate proves to be disadvantageous when a whole-body scan of a patient must be generated. In this case., the scan length presently available in computed tomography apparatuses is normally insufficient permit to scanning a patient without repositioning (i.e. a 180° rotation of the patient). Such a repositioning, however, significantly reduces the speed of the workflow, and it is additionally problematical that emergency patients are not able to reposition themselves. For this reason, such patients (together with the care devices connected to them) often must be first relocated to a second bed which is rotated by 180° in order to be able to subsequently position the patient again on the support plate of the patient positioning table of the computed tomography apparatus and scan the still-remaining body segment of the patient.